Friction Stir Processing of Cast Superalloys

This SBIR Phase I effort examines the feasibility of an innovative fabrication technology incorporating sand casting and friction stir processing (FSP) for producing affordable near net shape components made from high performance Ni-based superalloys. Sand casting is a relatively inexpensive casting method not traditionally used to manufacture superalloy castings. Instead of invested ceramic shells, the molds are produced from a mixture of fine sand and/or rammed graphite powder. Friction stir processing is an emerging microstructural modification technique based on friction stir welding (FSW). It can be applied to enhance the microstructure-properties of the cast material thus improve the damage tolerance capabilities. This step is needed to allow cast superalloy rocket propulsion components to be used without a casting factor.